// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GFX_GEOMETRY_POINT_H_
#define UI_GFX_GEOMETRY_POINT_H_

#include <iosfwd>
#include <string>
#include <tuple>

#include "build/build_config.h"
#include "ui/gfx/geometry/vector2d.h"
#include "ui/gfx/gfx_export.h"

#if defined(OS_WIN)
typedef unsigned long DWORD;
typedef struct tagPOINT POINT;
#elif defined(OS_MACOSX)
typedef struct CGPoint CGPoint;
#endif

namespace gfx {

// A point has an x and y coordinate.
class GFX_EXPORT Point {
public:
    Point()
        : x_(0)
        , y_(0)
    {
    }
    Point(int x, int y)
        : x_(x)
        , y_(y)
    {
    }
#if defined(OS_WIN)
    // |point| is a DWORD value that contains a coordinate.  The x-coordinate is
    // the low-order short and the y-coordinate is the high-order short.  This
    // value is commonly acquired from GetMessagePos/GetCursorPos.
    explicit Point(DWORD point);
    explicit Point(const POINT& point);
    Point& operator=(const POINT& point);
#elif defined(OS_MACOSX)
    explicit Point(const CGPoint& point);
#endif

    ~Point()
    {
    }

#if defined(OS_WIN)
    POINT ToPOINT() const;
#elif defined(OS_MACOSX)
    CGPoint ToCGPoint() const;
#endif

    int x() const
    {
        return x_;
    }
    int y() const { return y_; }
    void set_x(int x) { x_ = x; }
    void set_y(int y) { y_ = y; }

    void SetPoint(int x, int y)
    {
        x_ = x;
        y_ = y;
    }

    void Offset(int delta_x, int delta_y)
    {
        x_ += delta_x;
        y_ += delta_y;
    }

    void operator+=(const Vector2d& vector)
    {
        x_ += vector.x();
        y_ += vector.y();
    }

    void operator-=(const Vector2d& vector)
    {
        x_ -= vector.x();
        y_ -= vector.y();
    }

    void SetToMin(const Point& other);
    void SetToMax(const Point& other);

    bool IsOrigin() const { return x_ == 0 && y_ == 0; }

    Vector2d OffsetFromOrigin() const { return Vector2d(x_, y_); }

    // A point is less than another point if its y-value is closer
    // to the origin. If the y-values are the same, then point with
    // the x-value closer to the origin is considered less than the
    // other.
    // This comparison is required to use Point in sets, or sorted
    // vectors.
    bool operator<(const Point& rhs) const
    {
        return std::tie(y_, x_) < std::tie(rhs.y_, rhs.x_);
    }

    // Returns a string representation of point.
    std::string ToString() const;

private:
    int x_;
    int y_;
};

inline bool operator==(const Point& lhs, const Point& rhs)
{
    return lhs.x() == rhs.x() && lhs.y() == rhs.y();
}

inline bool operator!=(const Point& lhs, const Point& rhs)
{
    return !(lhs == rhs);
}

inline Point operator+(const Point& lhs, const Vector2d& rhs)
{
    Point result(lhs);
    result += rhs;
    return result;
}

inline Point operator-(const Point& lhs, const Vector2d& rhs)
{
    Point result(lhs);
    result -= rhs;
    return result;
}

inline Vector2d operator-(const Point& lhs, const Point& rhs)
{
    return Vector2d(lhs.x() - rhs.x(), lhs.y() - rhs.y());
}

inline Point PointAtOffsetFromOrigin(const Vector2d& offset_from_origin)
{
    return Point(offset_from_origin.x(), offset_from_origin.y());
}

// This is declared here for use in gtest-based unit tests but is defined in
// the gfx_test_support target. Depend on that to use this in your unit test.
// This should not be used in production code - call ToString() instead.
void PrintTo(const Point& point, ::std::ostream* os);

// Helper methods to scale a gfx::Point to a new gfx::Point.
GFX_EXPORT Point ScaleToCeiledPoint(const Point& point,
    float x_scale,
    float y_scale);
GFX_EXPORT Point ScaleToCeiledPoint(const Point& point, float x_scale);
GFX_EXPORT Point ScaleToFlooredPoint(const Point& point,
    float x_scale,
    float y_scale);
GFX_EXPORT Point ScaleToFlooredPoint(const Point& point, float x_scale);
GFX_EXPORT Point ScaleToRoundedPoint(const Point& point,
    float x_scale,
    float y_scale);
GFX_EXPORT Point ScaleToRoundedPoint(const Point& point, float x_scale);

} // namespace gfx

#endif // UI_GFX_GEOMETRY_POINT_H_
